The scope and mechanism of a reaction in which secondary amides are rapidly cleaved by reaction with diaryldialkoxysulfuranes is to be investigated with particular emphasis on selectivity factors operative in the cleavage of peptide links. New sulfurane reagents specifically tailored to provide desired reactivity patterns will be synthesized and their reactions studied, with particular emphasis on the reactions of amines and other compounds containing N-H bonds. A study of the relation between solvent structure in aqueous organic mixed solvent media and the solvent cage effect on free methyl radical production in the photolysis of azomethane will be continued. A new semiempirical relationship between fraction of radicals escaping the solvent cage and macroscopic solvent parameters will be perfected.